Process of producing certain proteids from buttermilk.



LUDWIG H. REUTER, OF BERKELEY, CALIFORNIA.

PROCESS OF PRODUCING CERTAIN PROTEIDS FROM BUT-TERMILK.

Specification of Letters Patent.

Patented Feb. 2, 190a.

Application filed January. 2, 1908. Serial No. 408,886.

To all whom it may concern:

Be it known that I, LUDWIG H. REUTER, a citizen of the United States, residing at Berkeley, in .the county of Alameda and State of California, have invented a new and useful Process of Producing Certain .Proteids from Buttermilk, of which the following is a specification.

Buttermilk, the by-product in the manu facture of butter from cream, is used to some extent for feeding calves, hogs, etc. where a relatively small amount is available,

but large butter-making establishments which have tofigure' with thousands of gallons of buttermilk as their daily byroduct durin the season, have met with di culties in fin ing any outlet for such a large quantit of Icy-product.

xperiments, which have been made heretofore for the purpose of separating casein from buttermilk have proved to be a failure, because the casein, obtained by heating the .buttermilk, did not dissolve in the usual casein solvents, and consequently such casein could not be used for technical purposes, as it did not, even if macerated in finest pulverized condition with alkali, yield a glue leavirig smooth surfaces when used for coating papers, or as an addition to cold water paints.

Now, I have discovered, that the above described insolubility of casein obtainedfrom buttermilk, is due to the resence in that casein of finely coa ulate milk albumen, and I have discovere' a process for subjecting the buttermilk to a chemical treatment, which in the end yieldscasein, soluble in the usual solvents, and useful for technical pur poses, and which allows at the same time the recovery of milk albumen, sugar. of milk, lactic acid, and lactates practically without decomposition.

Broadly speaking, my process consists in neutralizing the acid of the buttermilk by means of an alkali while in a cool condition so as to convert the casein into a soluble salt,

separating the milk albumen, and thereafter precipltatmg the casein. After the acid is neutralized, the process is lproceeded with by e mixture to dis solve t e casein and separate the milk-albumen, cooling, clarifying at a low temperature, and filtering. he filtrate is then heated moderately and the casein precipitated by an acid, preferab by sulfurous acid or an acid salt thereof. his method of kali compounds of the milk albumen.

precipitation after the neutralization-of the acid of the buttermilk is an important part of the .process. The second filtrate is used to make sugar of milk, lactic acid, and lactates, 6.

and the first press-cake for making milk albumen. Thus the buttermilk is separated into its constituent proteids, and pure casein, free from milk albumen is obtained.

In detailthe process may be carried out 6 in the following way :-Buttermilk, as obtained from the butter-maker, is put in an apparatus provided with a stirrer, a cooling coil, and a steam coil. Then while stirring, alkali, preferably sodium carbonate, is add- 7 ed for the purpose of neutralizing the free' lactic acid. Care should be taken not to heat the liquid, but to cool it preferably to about 32 F. until all the acid has been neutralized and the casein has been convert; ed into a soluble salt. If this part of the process is carried out at a higher temperature, the yield will not be as great, nor the, casein as pure. While stirring the liquid, it is desirable to take sam les'from time to time, and to add more a kali if necessary. Care must be taken also not to use an excess of alkali, as the same has the tendency of decomposing the casein and of formin ffi1ler 8 the stirring has been continued for, say, about an hour, the cooling is discontinued, the steam turned on, and the neutral li uid, stirring all the time, macerated for a out two hours at a temperature of about 150 F. I have found that in this time the casein dissolves properly and separates from the milk albumen. Finally, the liquid is heated only for about a minute to almost the boiling point for the purpose of separatmg more completely the milk albumen, then the steam is turned off and the liquid at once cooled. While ordinary cold water will suit the purpose for smaller operations, on a large scale I prefer to cool by means of refri eration, as for example, by means of a coil through which ice-cold brine or calcium chlorid solution, or. the like is passing. This process of cooling is also preferable Where the temperature ofthe ordinary water supply, in the summer-time, is too high, such asI have found is the case in some of the larger cities. As soon as the liquid has been clarified by settling at a low temIperature,1t is filtered through cloth, on the arger scale preferabl by means of a filter-press, in a clean tanlz provided with a steam coil. The

I filtrate is then heated to about 150 F, and

the radical (S0,), preferably sulfurous acid, or an acid sulfite, such as sodium bisulfite, in connection with sulfuric acid. Care must be taken to regulate the temperature carefully and not to go much above 150 F., as at higher temperatures milkalbumen, if such should still be resent in small quantities, might be coagu ated and precipitated together with the casein. The precipitated casein, thus obtained, can be washed with water, 'run through a curdmill, and be dried in a drying room provided with agood ventilator for the purpose of drawing 05 the moisture as quickly as possible. Casein, thus obtained, and properly disintegrated and ground, I have found to give a good glue, and to be especially valuable in connection with lime as an addition to cold water paints. The presence of a small quantity of sulfurous acid in the casein is an advantage, as it tends to preserve the casein, as well as glues prepared with the same.

The milk albumen obtained in my rocess by means of the filter-press is practically pure, and can be used for feeding purposes. The I presscakes should immediately be broken up and dried in a drying closet provided with a good ventilator;

The filtrate obtained by precipitating'the casein by means of sufurous acid, ll use. for

manufacturing sugar. of milk in the usual way, and I have dlscovered thatpractically no sugar of milk is lost by decomposition, even if an excess of sulfurous acid has been used to precipitate the casein, while it is an established fact that much sugar of milk is decomposed if, for instance, sulfuric acid is used for precipitating purposes. The mother liquor obtained in the sugar of milk manufacture I have used with advantage as a source for making pure medicinal lactic acid and lactates.

While I have described in detail a preferred way of carrying out the process, stating the temperatures which I have found to be most suitable, I am aware that many modificatlons may be made in carrying out the I process without departing from the scope of the invention as expressed in the claims. Therefore I do not wish to be limited in all respects to the details of the process as set forth above, but

What I do claim is r l. A process of treating buttermilk which consists in neutralizing the acid thereof at a low temperature, near 32 F., then heating above 100 F, and thereafter cooling and ounce filtering and subsequently precipitating the casein.

2. A process of treating buttermilk which consists in neutralizing the acid thereof at a low temperature, then moderately heating for a considerable period of time, then heating for a short time almost to the boilin point, thereafter cooling and filtering an subsequently precipitating the casein.

3. The process of treating buttermilk, which consists in neutralizing the acid thereof at a low temperature, heating to about 150 Fahrenheit for a period of more than an hour, then heating for about a minute to a temperature almost at the boiling point, then cooling, clarifying, and filtering and subsequently precipitating the casein.

4. A process of treating buttermilk which consists in adding-an alkali thereto, stirring and cooling to neutralize the acid of the but termilk, and converting the casein into soluble salt, heating moderately, macerating, and stirring under a moderate temperature to dissolve the casein and separate the milk albumen, then heating almost to the boiling point to more completely separate the milk albumen, at once cooling, clarifying and filtering and subsequently precipitating the casein. i

5. A process for treating buttermilk to separate it into its constituents which consists in adding an alkali thereto to neutralize the acid of the buttermilk, and converting the casein into a soluble salt, heating moderately, macerating, and stirring under a moderate temperature to dissolve the casein and separate the milk albumen, then heating almost to the boiling point to more completely separate the milk albumen, and at once cooling, clarifying and filtering, heating the filtrate to a moderate temperature, and precipitating the casein by sulfurous acid.

6. A process for treating buttermilk to separate it into its constituents which consists in adding an alkali thereto to neutralize the acid of the buttermilk, and converting the casein into a soluble salt, heating moderately, macerating, and stirring under a moderate temperature to dissolve the casein and separate the milk albumen, then heating almost to the boiling point to more completely separate the milk albumen, and at once cooling, clarifyin and filtering, heating the filtrate to a moderate temperature, precipitating the casein by sulfurous acid, and breaking up and drying the first press-cake to produce milk albumen.

7. A process of treating buttermilk which consists in neutralizing the acid thereof, heating, se arating the milk albumen, and thereafter ltering, heating the filtrate to a moderate temperature, and finally precipitating the casein therefrom.

8. A process of treating buttermilk which consists in neutralizing the acid thereof,

which comprises first neutralizing the acid 25 thereof, thereafter heatin to dissolve thecasein and separate the albumen, filtering, and finally precipitating the casein from the filtrate by sulflfi'ous-acid or an acid salt thereof.

heating, separatin the milk albmneirfiltering, heating the trate toa moderate tem rature, and finally precipitating the ymeans ofacompound containingv the rad1- cal (80 1 tk A process of buttermilk which consists in neutralizing the acid thereof,- heating, separatin the milk ,albumen, filter- 13.- As an article of manufacture, casein obtained from buttermilk by precipitation and initially free from coagulated milk albumen and soluble in the usual casein solvents when produced. 35 14. A composition. comprising casein obtained from buttermilk by preclpitation by 'sulfurous acid, and a small amount of sulfurous acid, said casein being soluble in the usual casein solvents.

In testimony whereof-I have hereunto.- set my hand, in the presence of two subscribing 'mg, heating the trate to a moderate tem- 10 perature, preciilpitating the casein, and breaking up an thefirst press-cake. 10. A process of treating buttermilk which consists in neutralizingthe acid thereof, at, about freezing point, then heating-labove" 15 blood heat, thereafter cooling and tering, breaking up and drying the press-cake, and

precipitating casein from the filtrate. v

11. A process of treating buttermilk ig'Ihichfcoriilprisefs3 firit neutraliziglg tllie' aclild witnesses.

ereo t erea er eati'n to sso ve t e i casein and separate-the m albumen, filter- LUDWIG. U

ing, and finally precipitating the casein Witnesses:

' W. A'.- Emmy; I Ror J. Young.

from the filtrate. r a v '12; process. -of treating buttermilk 

